The current project aims to describe the phenomenon of mitochondrial exchange in salmon and zebra fish - how this occur, analysis of transcriptomic and proteomic responses during mitochondrial exchange, and examine this phenomenon in vivo in a zebrafish model system. Mitochondria generate most of the chemical energy needed to fuel the cells biochemical reactions. It is clear that mitochondria also participate in innate defence against pathogens (viruses and bacteria) and are also able to produce signalling molecules central in the pathogen defence. It is also known that mitochondria can be transferred from one cell to another following cellular stress and tissue damage. How this transfer occurs is not clear yet, though there are indications that cells secrete vesicles and forms tunnels which may be a way of transfer. The project aims to characterise mitochondrial exchange by stressing cells by immunostimulants and nano plastics. Characterisation of mitochondrial exchange will be observed using high-end nanoscopy, whereas the cellular responses will be assessed by proteomic and transcriptomic analysis. The project will produce knowledge how cell may communicate with each other, what stressors that induce this phenomenon, and the biological impact this has on fish.
Salmon farming in Norway has grown dramatically over the last two decades – to 1.4 mill metric tons in 2019 (https://www.ssb.no/fiskeoppdrett). Despite this considerable progress, farmed salmon experience close to 20% mortality during the grow-out period in seawater. Fish suffer significantly from pathogens infections, physical insults and stressors contributing to approx. 20% overall mortality during the production. To re-establish homeostasis after infection and insults, tissue regeneration occurs. There is a major gap that the research on fish immunity needs to bridge for achieving the target of better fish health. This is to reach the same knowledge level as the mammalian systems about the role, criticality, and opportunities of exploiting the innate immune mechanisms of fishes. Research on innate immunity in higher vertebrates is continuously revealing multiple and highly conserved host–defense mechanisms. One of these is cell-to-cell communication (CCC) systems, wherein cell communicate with each other by virtue of receptor-ligand interaction and likely by exchanging organelles - such as mitochondrial exchange for rescuing and communication purpose. The current project aims to describe the phenomenon of mitochondrial exchange in salmon - how this occur, analysis of transcriptomic and proteomic responses during mitochondrial exchange, and examine this phenomenon in vivo in a zebrafish model system. Lack of resolution (in microscopy) is lack of knowledge. With this mission, the last decade has witnessed momentous progress in advanced microscopy. UiT has a unique position, where different advanced microscopy methods are brought together complemented by a strong research and development team. With the use of advanced microscopical methods we will examine the process of mitochondrial exchange at cell and tissue level.